Gate dielectric structures for integrated circuits and methods for making and using such gate dielectric structures

Abstract

Gate dielectric structures for integrated circuits and methods for manufacturing such gate dielectric structures are described. The gate dielectric structures contain gate oxide layers that are provided using a low temperature in-situ steam generation process, thereby providing silicon oxide layers of a very high quality. The gate oxide layers are used primarily in thin film transistors and as the bottom layer in the gate dielectric of silicon-oxide-nitride-oxide-silicon semiconductor devices.

We claim:  
     
         1 . A method for making a thin film transistor containing a gate dielectric structure, comprising: 
 providing a substrate for the gate dielectric structure; and    providing an oxide layer of the gate oxide structure on the substrate by an in-situ steam generation process.    
     
     
         2 . The method of  claim 1 , wherein the substrate comprises a gate conductor on a glass substrate.  
     
     
         3 . The method of  claim 1 , wherein the thin film transistor is a floating gate transistor or a SONOS transistor.  
     
     
         4 . The method of  claim 1 , wherein the in-situ steam generation process flows hydrogen and oxygen over the substrate.  
     
     
         5 . The method of  claim 1 , wherein the in-situ steam generation process is performed at a temperature ranging from about 600 to about 900 degrees Celsius.  
     
     
         6 . The method of  claim 1 , wherein the in-situ steam generation process is performed at a pressure ranging from about 100 millitorr to about 760 torr.  
     
     
         7 . The method of  claim 1 , wherein the in-situ steam generation process is performed for a time sufficient to deposit an oxide thickness of about 10 to about 200 angstroms.  
     
     
         8 . The method of  claim 1 , further including annealing the oxide layer in a nitric oxide atmosphere.  
     
     
         9 . A method for making a semiconductor device, comprising: 
 providing a substrate;    providing a first oxide layer on the substrate by an in-situ steam generation process;    providing a nitride layer on the oxide layer; and    providing a second oxide layer on the nitride layer.    
     
     
         10 . The method of  claim 9 , wherein the semiconductor devices is a SONOS transistor.  
     
     
         11 . The method of  claim 9 , wherein the in-situ steam generation process flows hydrogen and oxygen over the substrate.  
     
     
         12 . The method of  claim 9 , wherein the in-situ steam generation process is performed at a temperature ranging from about 750 to about 1050 degrees Celsius.  
     
     
         13 . The method of  claim 9 , wherein the in-situ steam generation process is performed at a pressure ranging from about 100 millitorr to about 760 torr.  
     
     
         14 . The method of  claim 9 , wherein the in-situ steam generation process is performed for a time sufficient to deposit an oxide thickness of about 10 to about 200 angstroms.  
     
     
         15 . The method of  claim 9 , further including annealing the oxide layer in a nitric oxide atmosphere.  
     
     
         16 . A method for making a gate dielectric structure for a thin film transistor or a SONOS device, comprising: 
 providing a substrate; and    providing an oxide layer of a gate dielectric structure on the substrate by an in-situ steam generation process.    
     
     
         17 . The method of  claim 16 , wherein the in-situ steam generation process flows hydrogen and oxygen over the substrate.  
     
     
         18 . The method of  claim 16 , wherein the in-situ steam generation process is performed at a pressure ranging from about 100 millitorr to about 760 torr and a temperature ranging from about 600 to about 1050 degrees Celsius.  
     
     
         19 . The method of  claim 16 , wherein the in-situ steam generation process is performed for a time sufficient to deposit an oxide thickness ranging from about 10 to about 200 angstroms.  
     
     
         20 . The method of  claim 16 , further including annealing the oxide layer in a nitric oxide atmosphere.  
     
     
         21 . A method for making a gate dielectric structure for a thin film transistor or a SONOS device, comprising. 
 providing a substrate;    providing an oxide layer of a gate dielectric structure, the oxide layer having a thickness of about 10 to about 200 angstroms; and    annealing the oxide layer in a nitric oxide atmosphere.    
     
     
         22 . A method for making a gate dielectric structure for a thin film transistor or a SONOS device, comprising. 
 providing a substrate;    providing an oxide layer of a gate dielectric structure on the substrate by an in-situ steam generation process performed at a temperature ranging from about 600 to about 1050 degrees Celsius, a pressure ranging from about 100 millitorr to about 760 torr, and for a time sufficient to deposit an oxide thickness of about 10 to about 200 angstroms; and    annealing the oxide layer in a nitric oxide atmosphere.    
     
     
         23 . A thin film transistor containing a gate dielectric structure made by the method comprising: 
 providing a substrate for a gate dielectric structure; and    providing an oxide layer of the gate dielectric structure on the substrate by an in-situ steam generation process.    
     
     
         24 . A SONOS semiconductor device made by the method comprising: 
 providing a substrate;    providing a first oxide layer on the substrate by an in-situ steam generation process;    providing a nitride layer on the oxide layer; and    providing a second oxide layer on the nitride layer.    
     
     
         25 . An integrated circuit containing a thin film transistor with a gate dielectric structure made by the method comprising: 
 providing a substrate for the gate dielectric structure; and    providing an oxide layer of the gate dielectric structure on the substrate by an in-situ steam generation process.    
     
     
         26 . An integrated circuit containing a SONOS semiconductor device made by the method comprising: 
 providing a substrate;    providing a first oxide layer on the substrate by an in-situ steam generation process;    providing a nitride layer on the oxide layer; and    providing a second oxide layer on the nitride layer.